Abstract 121P
Background
Ewing's sarcoma (EWS) is an aggressive bone and soft tissue tumor necessitating a multimodality approach for better survival. Comprehensive data on clinical spectrum and treatment outcomes are sparse from low and middle income countries (LMIC). To address this, we analyzed a 12-year cohort from a single academic cancer center.
Methods
Data of patients diagnosed with EWS and treated between Jan 2010 to Dec 2022 were retrieved from medical records and analysed.
Results
The study included 424 EWS patients, with 75.7% (n=321) having localized disease. The median age was 17 years, and 58.5% were male. The most common tumor locations were the chest wall (12%) and pelvic bones (11.3%). Extraskeletal EWS was seen in 34.2% (n=145). Pain (94.8%) and swelling (74.3%) were the most common symptoms. Bulky tumors (>8 cm) were found in 27.8% (n=118) cases. Diagnosis was predominantly by histopathology and immunohistochemistry. Fluorescent in situ hybridisation (FISH) was done in only 8.5% of cases due to financial constraints. Among localized disease cases, only 63% (n=202) completed the planned treatment. Treatments included neoadjuvant chemotherapy (NACT) in 88.8% (n=285), surgery in 40.5% (n=130), radiotherapy in 59.5% (n=191), and adjuvant chemotherapy in 94.7% (n=304). Tumor necrosis >90% was seen in 60% of post NACT resected specimens. The median follow-up was 70 months, with 222 patients (60%) being alive. The median overall survival (OS) for localised and metastatic disease was 112 months and 23 months respectively. For localized disease, the 5 year and 10 year event free survival (EFS) was 45% and 41% respectively, while OS at 5 year and 10 year were 65% and 45% respectively. For metastatic disease, the 5 year OS was 18%. On multivariate analysis, metastatic disease, marrow involvement, incomplete treatment, and recurrence were associated with worse outcomes.
Conclusions
This study represents the largest single center experience. Socio-economic challenges lead to delay in timely access to appropriate care, treatment compliance and follow up. Accessibility and affordability of advanced diagnostics and therapies are a limitation. Despite these, EFS and OS were better than in other studies.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.